Science Buddies: "Ask an Expert"

Going Green as You Clean: Are 'Green' Detergents Less Toxic Than Conventional Detergents?

I have about six months for this project..... I will post on how to do this project very soon!

Abstract

There is strong interest in "going green," including using products that cause less environmental damage when they are disposed of. In this environmental sciences project, I will compare the toxicity of "green" and conventional liquid detergents using worms as test organisms.

Objective

The objective of this environmental sciences project is to determine if green detergents are safer for the environment than conventional detergents.

Introduction

Reduce, reuse, recycle. These are typically known as the three R's of the environment. Every year, Americans throw away billions of containers and other packaging materials that end up in landfills. Reducing the amount of waste you produce is one way to help the environment. Another way to help the environment is to recycle. Many of the things we use every day, like paper bags, soda cans, and milk cartons, are made out of materials that can be recycled. Recycled items are put through a process that makes it possible to create new products out of the materials that come from the old ones.

Reusing is another way to help protect the environment. The idea is simple: instead of throwing things away, try to find ways to use them again. The use of grey water to irrigate plants is an example. Grey water is the water produced by showering, cleaning clothes, washing dishes, etc. It does not include human waste (that is called black water, and is not safe to use for irrigation). Clearly, if grey water is to be used for growing plants, the kinds of detergents used in the house will have to be eco-friendly. In other words, the detergents used should cause little or no environmental damage.

If water is to be successfully reused to irrigate plants, it is critical that the reused water not be harmful to worms and other creatures that are important for the health of the soil. In this environmental science fair project, you will compare the toxicity of "green" (those asserting they are environmentally friendly) and conventional dishwashing detergents by measuring their effects on worms.

I got this idea from the topic selection wizard. For more details the name of it is 'Going Green as You Clean: Are 'Green' Detergents Less Toxic Than Conventional Detergents?'

I'm not very sure how my hypothesis should go.

Kelsey

Hi Kelsey,

Welcome back to Science Buddies! It’s great that you are interested in doing another science project.

The green detergent project measures the relative toxicity of regular and green detergents on earthworm activity and survival.

https://www.sciencebuddies.org/science- ... p053.shtml

Since you are starting this project early, you could also do a similar project with plants:

https://www.sciencebuddies.org/science- ... p040.shtml

A couple of comments on the project as it is outlined. The project calls for using worms from a bait store. You should check and make sure you get fresh worms that are active. Starting with fesh, actively growing worms will help with this project. Also, the outline calls for using a very large number of dilutions for each detergents. I think you could probably find information about the expected toxicity of various concentrations of detergents that might cause toxicity, as that would allow you to, for example, skip the more concentrated samples.

This first step in your project is do to a little more background reading so you can understand what the problem is with regular detergents, and what the difference is between regular and green detergents. This information will help you formulate a question that you can answer with a controlled experiment.

First, it will be helpful if you understand what a detergent is. Have you had any chemistry yet?

Here’s basic information on how detergents work:

http://chemistry.about.com/od/howthings ... entfaq.htm

The Wikipedia article has a good explanation of how detergent work:

http://en.wikipedia.org/wiki/Surfactant

Here is basic information about explaining why detergents are toxic:

Here’s an abstract of an article that studied the toxicity of various laundry detergent ingredients:

http://www.sciencedirect.com/science/ar ... 1399918249

Here are some laundry detergent ingredients that the US. EPA is concerned about:

http://www.greenbiz.com/news/2010/08/19 ... -chemicals

Here’s an abstract describing the toxicity of laundry detergent to fish:

http://onlinelibrary.wiley.com/doi/10.1 ... x/abstract

I cannot find a scientific reference for green laundry detergents right now, but here is some general information with links for additional reading.

http://laundry.about.com/od/ecofriendly ... rgents.htm

And here is an article written by a chemist on the subject:

http://www.sciencebase.com/science-blog ... gents.html

Please notice that I’ve tried to include mostly information from or based on scientific literature. Scientific literature sources are always better for science projects.

Also, it is not too early to consider how you will analyze your data. You need to plan experiments that will include a sample size that large enough so that your results will be statistically significant:

https://www.sciencebuddies.org/science- ... ysis.shtml


Here are some questions I can think of at this point.

1. What detergents are you interested in testing?
2. Are you interested in testing a specific ingredient in laundry detergent?
3. What is the chemical composition of the detergents you are planning to test?
4. What question do you want to answer with your experiment?



I hope this will help you get started. Please let me know if you have any questions.


Donna Hardy

Hi Donna,

Thanks for the link for the similiar project for plants..... but since its my last science fair at my school I really want to challenge myself and go above and beyond. I checked the difficulty level of the plants and it was only fifth grade so I'm going to give my best to the worms project. The other links and advice helped a lot. I will most likely begin this project in a month or so. The sooner the better!

- Kelsey

By the way.... I have not done much work with chemistry but I should learn some about it before and during the project because in science class we are learning about chemistry. I am not sure which detergents I am going to test.

Hi Kelsey,

It’s good to get started early so you will have time to do your experiment at least twice. Before you start, you need to find a question that is worthwhile answering and then carefully design your experiment to answer that question. There are lots of ingredients in laundry detergent, so I recommend selecting one ingredient to test. Or, you could contact your local water treatment plant and ask for someone you could interview; perhaps you could identify a project that would be of significance in your local community. You need to find the chemical structure of the detergent molecules you are going to test and understand how detergents work to clean clothes and why these molecules can be toxic to wildlife. You need to know the expected concentration of detergents in water so you can design your experiment to match expected conditions. You need to learn everything you can about earthworms. The best science fair projects have really good background information explaining the significance of the project. So, do read as much as you can about your topic and I'm sure you will find a good question to ask that will be answered by your experiment.


Donna Hardy

Kelsey,
Donna has provided some great information for you. One thing you might want to do some research on first is what differences are there between "green" detergents and standard detergents? Is it simply a marketing strategy and there are really no differences? I am not sure, but it would be interesting to learn more about how they compare. How many different detergents are you going to test?

Matt Badtke

Hi,

Okay, I'm doing research today and I hope to have a rough draft or basic research done by the end of the day. If anyone comes across websites about the environment, pollution, detergents, and eco-friendly detergents please post them here. If you have anything that would have anything to do with this project please post them here.

Thanks,
Kelsey

Hi Kelsey,

All of the links that I previously posted would be provide background information for your research paper. Basically, what you want to accomplish in the research paper is to explain the scientific principles behind your project and describe the problem you are trying to solve. In the last paragraph, you can describe in general what you are going to do to answer your research questions, but you should not include a detailed protocol at this point.

Here is the information on research papers from the Science Buddies website, which includes additional tips.

http://www.sciencebuddies.com/science-f ... aper.shtml

Good luck!


Donna Hardy